Have you done any other research into this?
I'm not terribly familiar with the world of hosting, or whether it's different in other countries, but there was a documentary about this a while back that was rather interesting... this one I think:
From what I can tell, the real money in hosting comes from accruing a regular clientele and fostering the illusion of an emotional relationship with them, a sort of empty promise that amounts to a hollow reflection of actual human connection.
Apparently a lot of the clients at host clubs are hostesses or sex workers themselves, looking for a place to unwind without judgment and get some of that feeling they sell to their own clients. This creates a vicious cycle where the girls must stay in the industry to be able to afford their habits. All the while, it seems like the business themselves are the only ones making any real profit from all this. On a personal note, I find all this rather demented, but fascinating at the same time. If anything it's a testament to the need for connection. There are all kinds of different people out there, google "financial dominatrix" for something really crazy.
For your situation, I can't imagine a host club that would sponsor a visa, and most club owners probably don't even know how to go about doing it because it's not a routine process for them. This hardly qualifies as legitimate work, and I'm guessing the majority of a host's income is actually under the table. The type of people that run these clubs are the same no matter where you go; you will be exploited. It seems like it's not altogether unheard of (there's quite a lot of comments here, but it IS the internet so who knows what is true:
I am addicted to Host Clubs. : japan but foreign hosts are a very small minority who probably already have their visas sorted out... perhaps kept on as either a novelty or for the small minority of non-Japanese clients. Reread my first paragraph, and then ask yourself how much demand you could generate from clients if you don't share a common language. Good looks and body language can only get you so far. Now put yourself in the shoes of a club owner, who somehow gets contacted by some kid who doesn't speak the language but wants to come work in the club. His resume includes working illegally (unknowingly) in some other asian country. Would you sponsor his visa?
If you can legitimately work in Singapore, you would probably have better luck there, as English is a common language there and your language skills wouldn't put you at such a disadvantage. Best of luck, and perhaps come back and let us know how things go for you. We often get these fly-by questions and rarely do we ever learn what becomes of people.